|HazOp Risk assessment decision tool
Cauldon suffered an explosion in the electrostatic precipitator during light-up after the 2009 shutdown. The HSE investigation identified that the incident could have been avoided if a HazOp study on the kiln feed elevator project had been carried out.
Cauldon’s approach to HazOp had been to only use this when dealing with hazardous substances or fuels. The Cauldon team agreed that a tool was needed to identify the level of risk assessment required on future projects. An excel spreadsheet was developed to use as a scoring system to identify what level of risk assessment should be used.
The tool has been used for all recent projects and has led to HazOp being conducted on a formal basis. It also highlighted that specialist knowledge was needed for certain projects and that the facilitation of a HazOp needs a level of competence that was not currently available on site.
The tool developed is based on 18 questions, each question being answered ‘yes’ scores one point, the final score determining the level of risk assessment required. The HSE judged that the tool satisfactorily identified the level of assessment needed. The tool, when used retrospectively on the project that indirectly led to the precipitator explosion, showed that a HazOp would have been needed and would have identified a number of specific issues relating to other equipment in the process.
Improvement to safety by:
A check list of relevant safety questions prior to work commencing
A facility for any ‘no’ answers to be clearly identified in a well documented system to support the decision
On completion of the work, a form to identify relevant questions to ensure the working area is left safe, clean and green
The form is user friendly.
Greater efficiency has also been achieved:
The form has been designed to incorporate basic information i.e. purchase order numbers to ensure the contractor is working with an order number
The booklet is in triplicate enabling the contractor to have a copy ensuring the unique number can be followed through on the invoice.